The present invention relates generally to trainline communications and more specifically, to the serialization of cars in a train.
With the addition of electropneumatically operated train brakes to railway freight cars comes a need to be able to automatically determine the order of the individual cars and locomotive in the train. In an EP brake system utilizing a neuron chip or other "intelligent circuitry", a wealth of information is available about the status of each car and locomotive in the train. But unless the location of the car or locomotive in the train is known, the information is of little value. It has been suggested that each car or locomotive report in at power-up. While this provides information on which cars and locomotive are in the train consist, it does not provide their location in the consist. Also, in some trains, the direction the car or locomotive is facing or orientation in the train is required. Typical examples are rotary dump cars and remotely located locomotives.
Present systems address this issue by requiring that the order of the cars in the train be manually entered into a data file in the locomotive controller. While this does provide the information necessary to properly locate each car in the train, it is very time consuming when dealing with long trains, and must be manually updated every time the train make-up changes (i.e. when cars are dropped off or picked up). The present invention eliminates the need for manually entering this data by providing the information necessary for the controller to automatically determine the location of each car and EP control module or node in the train.
Historically, there has only been a communication link between one or more of the locomotives in a train with more than one locomotive needed. Current EP systems require a communication link between all cars and locomotives in a train or consist. The Association of American Railroads has selected as a communication architecture for EP systems, LonWorks designed by Echelon. Each car will include a Neuron chip as a communication node in the current design. A beacon is provided in the locomotive and the last car or end of train device to provide controls and transmission from both ends of the train.
The serialization of locomotives in a consist is well known as described in U.S. Pat. No. 4,702,291 to Engle. As each locomotive is connected, it logs in an appropriate sequence. If cars are connected in a unit train as contemplated by the Engle patent, the relationship of the cars are well known at forming the consist and do not change. In most of the freight traffic, the cars in the consist are continuously changed as well as the locomotives or number of locomotives. Thus, serialization must be performed. more than once.
The present invention is an automatic method of serialization by establishing a parameter along a length of the train between a node on one of the cars and one end of the train. The presence or absence of the parameter at each node is determined and the parameter is removed. The sequence is repeated for each node on the train. Finally, serialization of the cars and orientation of at least one car are determined as a function of the number of either the determined presences or absences of the parameter for each node.
The parameter can be established by providing, at the individual node one at a time, an electric load across an electric line running through the length of the train. Measuring an electrical property, either current or voltage, at each node determines the presence of the parameter. Each node counts the number of presences or absences of the parameter determined at its node and transmits the count with a node identifier on the network for serialization. The line is powered at a voltage substantially lower than the voltage at which the line is powered during normal train operations.
To determine the orientation of a car within the train in a first embodiment, a local node may be provided with a primary and secondary node adjacent a respective end of the car. In the sequence, the parameter is established for the car having a primary and secondary node using at least the primary node. Determination of the presence or absence of the parameter uses both primary and secondary nodes. The use of the primary node alone to establish the parameter is sufficient to determine the orientation of the car. Alternatively, both the primary and secondary node may be sequentially activated to establish a parameter.
Another method of determining orientation according to a second embodiment is establishing a parameter at one node and detecting the presence or absence of the parameter at that node. If the parameter is present, the car has one orientation and if absent, the car has the opposite orientation.
Prior to establishing a parameter along a length of the train, a count of the number of the cars in the train and their identification of each car is obtained. After the sequence of establishing the number of presences or absences of the parameter for each car is completed, the count of the number of the cars in the train is compared with the number of cars which transmit a count. Preferably, determining the presence or absence of the parameter includes determining the presence or absence of the parameter at each node except for the node which has established the parameter.
Testing operability of the nodes includes establishing a parameter along the length of the train and determine the presence or absence of the parameter at each node. The parameter is then removed and the presence or absence of the parameter at each node is again determined. Operability of the node is determined as a function of either the presences or absences of the parameter which was determined for each node.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.